

A new image of the new creature - commonly referred to as "Endermen" - was released recently (enhanced here, for light levels). This image is much more up-close-and-personal than the first, giving us a good look at the new creatures. It would seem that wearing a pumpkin prevents the new mob from seeing you, although this is unconfirmed at present.
Additionally, Notch mentioned a possible name-change for the newly minted mob, "Farlander" being suggested and, apparently, already in heavy use.
In short: If you get too close, they attack anyways.
Plus, you already have the Far Lands. It's creepy enough as it is, so it makes sense for the mob to originate there.
Millenaire seemed to do it without a problem, whats stopping Notch? ;3
I would try to explain it you, but it's pretty deep. You wouldn't understand.
Endermen sound like some gay ass superhero.